Hi John,
I can't speak for salmon, but No 2 Mepps do very well for sea-trout.
For local info you can check with the tackle-shop in Bishop Aukland (can't remember their name).
Since this is a fly forum I should mention that tube-flies with blue and black in them do well on the Wear, as does anything with a bit of silver in it if the river is fining down after a spate.
I love the fly, but I have to admit to hankering after a no 2 Mepps, no weight on the line, flicked upstream and under the far bank on a 7' rod. When a 5lb+ fish takes you really know about it! Parts of the Wear are perfect for this type of fishing. Perhaps I can find a nice cane spinning rod......

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Anyway, Page Bank is a good beat for sea-trout. The big fish are probably through the system by now but there should be a few 4/5 lb-ers still coming through.
The main run starts in July though, so you may be a bit late.
I advise spending a few days fishing the water to familiarise yourself with it for next year. You may get lucky and hit a fish or two.
DB